Hair Care and Hairstyling
What this domain tests
The Hair Care and Hairstyling items ask you to connect hair structure to product choice, scalp analysis to service safety, and styling method to the finished shape. Expect questions on cuticle and cortex function, porosity and elasticity, shampoo and conditioner chemistry, and wet versus thermal styling.
Core concepts
- Structure: the cuticle is the protective outer scale layer; the cortex holds keratin, melanin, and bonds; the medulla is the central core and may be absent in fine hair.
- pH: hair and scalp sit near pH 4.5–5.5. Alkaline shampoo swells the cuticle; acidic conditioner smooths it.
- Hair analysis: texture is strand diameter; density is hairs per square inch; porosity is the ability to absorb and retain moisture; elasticity is stretch-and-return. Poor elasticity is a warning against chemical services.
- Conditioning: moisturizing ingredients attract water; protein ingredients temporarily fill gaps in damaged cortex. Neither repairs hair permanently.
- Styling: wet styling uses tension and molding, as in finger waves, pin curls, and braids; thermal styling uses heat, so a heat protectant and controlled temperature matter.
Worked example
A client with over-processed, high-porosity hair wants a sleek blow-dry. High porosity means the cuticle is raised, so hair absorbs quickly and loses moisture fast. Choose a low-pH conditioner, apply a heat protectant, use low heat and moderate tension, and avoid a strong alkaline shampoo. Recommend a trim rather than another chemical service.
Traps that cost marks
Do not confuse porosity with density. Do not claim conditioner repairs hair. Do not recommend medicated shampoo without a scalp condition that calls for it. Remember that cool water and cool air help close the cuticle after heat styling.